20,202 research outputs found
Matrix Transfer Function Design for Flexible Structures: An Application
The application of matrix transfer function design techniques to the problem of disturbance rejection on a flexible space structure is demonstrated. The design approach is based on parameterizing a class of stabilizing compensators for the plant and formulating the design specifications as a constrained minimization problem in terms of these parameters. The solution yields a matrix transfer function representation of the compensator. A state space realization of the compensator is constructed to investigate performance and stability on the nominal and perturbed models. The application is made to the ACOSSA (Active Control of Space Structures) optical structure
Commencement Address: Winter Quarter, 2002
Commencement address given by David L. Brennan, Chair of the OSU Board of Trustees, to the Winter 2002 graduating class of The Ohio State University, St. John Arena, Columbus, Ohio, March 15, 2002
Teaching Reproducibility to First Year College Students: Reflections From an Introductory Data Science Course
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Modern technology threatens traditional modes of classroom assessment by providing students with automated ways to write essays and take exams. At the same time, modern technology continues to expand the accessibility of computational tools that promise to increase the potential scope and quality of class projects. This paper presents a case study where students are asked to complete a “reproducible” final project in an introductory data science course using the R programming language. A reproducible project is one where an instructor can easily regenerate the results and conclusions from the submitted materials. Experiences in two small sections of this introductory class suggest that reproducible projects are feasible to implement with only a little increase in assessment difficulty. The sample assignment presented in this paper, along with some proposed adaptations for non-data science classes, provide a pattern for directly assessing a student’s analysis, rather than just the final results
Interval-Valued Kriging Models with Applications in Design Ground Snow Load Prediction
One critical consideration in the design of buildings constructed in the western United States is the weight of settled snow on the roof of the structure. Engineers are tasked with selecting a design snow load that ensures that the building is safe and reliable, without making the construction overly expensive. Western states use historical snow records at weather stations scattered throughout the region to estimate appropriate design snow loads. Various mapping techniques are then used to predict design snow loads between the weather stations. Each state uses different mapping techniques to create their snow load requirements, yet these different techniques have never been compared. In addition, none of the current mapping techniques can account for the uncertainty in the design snow load estimates. We address both issues by formally comparing the existing mapping techniques, as well as creating a new mapping technique that allows the estimated design snow loads to be represented as an interval of values, rather than a single value. In the process, we have improved upon existing methods for creating design snow load requirements and have produced a new tool capable of handling uncertain climate data
MUSCLE SYNERGY DURING A SINGLE LEG STANDING TEST IN AMBULATORY CHILDREN WITH CEREBRAL PALSY
INTRODUCTION: Cerebral Palsy (CP) is a sensorimotor disorder characterized by dysfunctional motor coordination, balance problems, and loss of selective motor control. Motor coordination exhibited as co-contraction, has been subjectively quantified using gait analysis, but recent studies have begun to objectively analyze the amount of co-contraction by collecting electromyography (EMG) data. Center of pressure excursion (COPE) measurements collected during a single leg standing test (SLST) have shown to be more valid measurements of balance in populations with motor disabilities than a SLST alone. A recent study has correlated increased COPE velocity with a lower fall risk as determined by reported fall frequency, suggesting a more objective measure of fall risk. The current study aimed to determine if the fall risk calculated by COPE velocity in children with CP is correlated with co-contraction index value in various muscle synergy groups. It was hypothesized that i) co-contraction index values will differ between high and low fall risk groups, ii) there will be preferential activation of different synergy groups within the high and low fall risk groups, and iii) there will be a negative and direct correlation between COPE velocity and co-contraction index values for all synergy groups. METHODS: Fall risk grouping was determined by average COPE velocity values calculated from previously reported fall frequency groups. Balance ability was determined by COPE measurements during a SLST on a force plate. Muscle synergy groups were determined by common muscle pairings at the hip, knee and ankle. Co-contraction indices were determined from linear envelopes plotted from muscle group EMG data. An independent t-test was run on muscle synergy groups between high and low fall risk groups. Nonparametric Analysis of Variance (ANOVA) and Tukey post-hoc tests were run on the high and low fall risk groups separately to determine differences in co-contraction index value within high and low fall risk groups. A Pearson correlation analyzed COPE velocity and co-contraction index value. RESULTS: No significant differences in muscle synergy between the high and low fall risk groups were found (p = 0.476, 0.076, 0.064, 0.364). The ANOVA and Tukey post-hoc tests for high fall risk group found significant differences in co-activation index value between the sagittal hip and frontal hip groups (p = 0.022) and sagittal hip and ankle groups (p = 0.016). Low fall risk group was found to have significant differences between the sagittal hip and frontal hip groups (p = 0.038) and frontal hip and knee groups (p = 0.012). Weak and negative correlations were found between COPE velocity and both knee and ankle groups (r = -0.309, -0.323, p = 0.059, 0.050). Negligible and insignificant correlations were found between frontal hip and sagittal hip synergies and COPE velocity ((r = 0.013, -0.068, p = 0.475, 0.367). CONCLUSION: There is insufficient evidence to claim that muscle group activations are different depending on fall risk grouped by COPE velocity. It is not currently possible to correlate COPE velocity to a specific synergy group recruitment. However, data do suggest that sagittal hip and knee strategies are recruited more than ankle and frontal hip strategies during SLST
Determining Trademark Standing in the Wake of \u3cem\u3eLexmark\u3c/em\u3e
This Note examines relevant statutory language, case law, and scholarly criticism, and ultimately contends that the standard articulated in Lexmark should apply to both types of claims. Part I provides background regarding the history of the Lanham Act, looking particularly at the ways in which courts have treated trademarks and false advertising differently. Part II discusses the Lexmark decision and the recent district court cases that have addressed its holding. Part III examines the text of both the Lanham Act and the Supreme Court’s opinion in Lexmark in order to determine the decision’s scope, and concludes that Lexmark’s holding applies equally to false advertising and trademark claims. Finally, Part IV, which is divided into two subsections, advances policy-based arguments for such a uniform application of the Lexmark standard. Generally, Part IV discusses the expansive nature of modern trademark law and explores the ways in which Lexmark’s standing requirement might serve as a narrowing force. First, Section IV.A laments the lack of a materiality requirement in trademark law and demonstrates how Lexmark’s proximate cause requirement might make up for that absence. Section IV.B focuses specifically on one area of application in trademark law—the initial interest confusion doctrine—and suggests that Lexmark, if properly applied, could possibly eliminate this doctrine
Development of Prediction Models to Estimate 1-RM for Upper and Lower Body Exercises in Non-Resistance Trained Women
PURPOSE: The purpose of this investigation was to develop and validate a one-repetition maximum (1-RM) prediction model for the upper and the lower body in non-resistance trained women. METHODS: Sixty seven healthy, non-resistance trained women between the ages of 18 and 25 years volunteered for this investigation. The investigation was performed in 2 phases. During phase I, all subjects completed 2 experimental sessions. During the first session, subjects performed a bench press repetition to fatigue (RTF) test with 45 lb and 55 lb. Subjects also performed a leg press RTF with 175 lb and 215 lb. Additional variables that were measured were: body height (in.), body weight (lb), and sum of skinfolds (mm). During the second session, subjects performed a 1-RM bench press and a 1-RM leg press. Phase II of the experiment involved the development and validation of 1-RM prediction models for the bench press and the leg press exercise. RESULTS: A stepwise regression analysis was carried out to develop a 1-RM prediction model for the bench press exercise and for the leg press exercise. The initial set of predictor variables considered for the upper body prediction model were: RTF with the bench press, body height (in.), body weight (lb), and sum of skinfolds (mm). The variable selected by the stepwise regression analysis for inclusion in the bench press prediction model was RTF with 55 lb (r = 0.914). The model to predict 1-RM bench press was: Model I: 1-RM bench press = 56.199 + 1.94(RTF55). A paired samples t-test indicated that the difference between the mean measured and mean predicted 1-RM was not significant (p>.05). The correlation between the measured and the predicted 1-RM values for the bench press was r = 0.935. The initial set of predictor variables considered for the lower body prediction model were: RTF with the leg press, body height (in.), body weight (lb), and sum of skinfolds (mm). The variables selected by the stepwise regression analysis for inclusion in the leg press prediction model were RTF with 215 lb and body weight (lb) (r = 0.798). The model to predict 1-RM leg press was: Model II: 1-RM leg press = 145.099 + 2.752 (RTF215) + .618 (body weight). A paired samples t-test indicated that the difference between the mean measured and mean predicted 1-RM was not significant (p>.05). The correlation between the measured and the predicted 1-RM values for the leg press was r = 0.695. CONCLUSION: The models developed in this investigation can be used to estimate the upper and/or lower body 1-RM strength of non-resistance trained women. These models will be useful for coaches, personal trainers, and fitness professionals who wish to design strength-training programs to enhance performance and the health-fitness levels of recreationally active females
Singing Behavior and Geographic Variation in the Songs of the Veery (Catharus Fuscescens) Across the Appalachian Mountains
The Veery (Catharus fuscescens) is a common Neotropical migrant thrush whose breeding distribution spans the Northern United States and southern Canada and continues south through the high elevations of the Appalachian Mountains. Despite its wide distribution, many aspects of Veery biology are largely unknown, including a clear characterization of song and knowledge of geographic song variation. I describe the song structure, repertoire size, and patterns of song delivery in the songs of the Veery and describe geographic song variation across four regions along the Appalachian Mountains. Visual analysis of song spectrogram images of territorial males revealed that Veeries\u27 repertoire ranges from one to six different song types, which is larger than what was previously described in the literature. Spectrogram analysis suggested that Veeries present song types in predictable patterns, and patterns of song presentation can change depending on repertoire size. Veeries also presented their songs in an oscillating frequency pattern regardless of repertoire size, a previously undocumented feature of their singing behavior. Random coefficient models show significant variation infrequency and temporal features of the Veery song within each sample area and across the Appalachian Mountains. The interconnectedness of developmental and behavioral processes such as song learning, natal and breeding dispersal, and varying levels of gene flow among populations may be influencing the geographic frequency shifts found in Veery songs across this more isolated portion of the breeding rang
The Robes of the Medical Royal Colleges and Other Societies: Medical Education ouside the Universities
In his book English University Life in the Middle Ages Alan Cobban remarked on the theoretical nature of medical education in the Middle Ages. Many men who graduated were more interested in teaching the subject than in the practice of medicine. A more practical approach would be gained from Continental centres, Padua and Leiden, but the non-academic bodies in London, the two Royal Colleges and the Society of Apothecaries would play an important part. The author assesses and analyzes how the formation of the profession would influence the development of ceremonial robes outside the two ancient universities. [Excerpts]
Validation of Macro Button Toolbar System for Radiology Report Composition
The macro button toolbar system was developed to enhance radiologist report composition and improve group productivity in response to a rise in imaging volume and an impending radiologist workforce shortage. This research aims to validate the proposed benefits of the macro button toolbar system using an analysis of a time study and the radiology group’s historical wRVU productivity data. The study found that radiologists using this system achieved significantly higher productivity compared to national averages, with high toolbar users experiencing a 29% increase in wRVU productivity and a 52.6% reduction in report completion time for X-ray exams. The reduced report completion time for x-ray exams allows radiologists to focus on more complex reports and examinations that do not utilize the macro button toolbar system as fully and therefore increase daily productivity
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